The governing board of the University of Missouri on Thursday named a black law professor and deputy chancellor emeritus to serve as interim president of a university system under siege from racial turmoil.

Michael Middleton, who recently retired from the university after 30 years, earned bachelor and law degrees there. His selection came three days after Tim Wolfe resigned amid a firestorm over his handling of a series of racially charged events on the sprawling campus in Columbia.

"We all must heighten our focus, improve our culture ...and share the responsibility to see our university advance in healthy ways built upon respect for others," Middleton said. "I am energized. We need to get our community together, working together."

MIddleton, 68, promised that incidents of racial harassment will be dealt with quickly.

"We hope at some point this kind of turmoil will dissipate," he said.

Controversy has swirled on the embattled campus in recent weeks as students held protests demanding Wolfe be fired. The issue blasted onto the national scene Saturday, when more than 30 of the school's football players announced a boycott of football-related activities. The deans of several academic departments also had called for Wolfe to go.

"We are excited for the new leadership under Interim President Middleton!" tweeted Concerned Student 1950, an advocacy group named for the year the school admitted its first black student.

On Monday, Wolfe announced his resignation effective when a replacement could take over the job. Campus chancellor R. Bowen Loftin also resigned; an interim chancellor already has been named.

Wolfe's detractors accused him of inaction following a spate of incidents on the 35,000-student campus. Student government president Payton Head, who is black, said that in September people in a passing pickup shouted racial slurs at him. In October, members of a black student organization said slurs were hurled at them by an apparently drunken white student. In addition, a swastika drawn in feces was found recently in a dormitory bathroom.

On Thursday, University of Missouri Police said they were investigating vandalism at the school's Gaines-Oldham Black Culture Center. The incident came one day after police arrested students at two Missouri campuses accused of issuing threats on social media.

Northwest Missouri State University student Connor Stottlemyre, 19, was arrested on suspicion of making a terrorist threat after he allegedly posted a threat on the anonymous social media app Yik Yak that read "I'm going to shoot any black people tomorrow, so be ready," university spokesman Mark Hornickel said. Police also arrested Hunter Park, 19, a student at the University of Missouri's Rolla campus, and charged him with making terrorist threats for allegedly posting messages suggesting he was going to do harm to black students on the Columbia campus.

A Columbia campus associate professor, Dale Brigham, offered to resign after facing backlash for calling on his students to show up for class despite the threats, which had caused some African-American students to leave campus. Brigham expressed regret for sending an email to students in his nutritional science course encouraging them not to let "bullies" win.

Christian Basi, a university spokesman, told USA TODAY in an email Thursday that Brigham is still employed at the university and would not comment on the status of his resignation offer. KOMU was reporting that the school had declined to accept the resignation.

Another staff member has been placed on leave pending an investigation of her actions during protests on campus.

Janna Basler, director of the Columbia campus' Greek Life, was among students, faculty and staff who were trying to keep reporters away from protesters with the group Concerned Student 1950. Video of Basler shows her berating and having physical contact with student-journalist Tim Tai, who was on assignment for ESPN and trying to take photographs of the scene.

Also on the hot seat is Melissa Click, an assistant professor in the Department of Communications. A student who filmed Click calling for "muscle" to eject him from a protest site on campus filed a complaint alleging simple assault. Mark Schierbecker said he was waiting to hear whether campus police would press charges.

"We are looking into this and following up," police department spokesman, Maj. Brian Weimar said.